1. Field of the Invention
This invention is concerned with the installation of door furniture, particularly door handle and latch assemblies.
2. Description of Prior Art
A door handle assembly generally comprises a pair of handles disposed one to each side of the door and mounted on a shaft which extends through a transverse hole in the door and through a latch installed in the door so that its bolt can extend from the outer edge of the door but can be retracted by rotation of the handle shaft. A pair of escutcheon plates are mounted against the side faces of the door to cover the hole through which the handle shaft passes. In some cases the escutcheon plates are simply attached to the door by means of screws which remain visible but in other constructions a concealed mounting is achieved. One example of a concealed mounting is disclosed in Australian Patent No. 409,156 in which each escutcheon plate is screw fitted to a mounting plate which is fixed to the door and covered by the escutcheon plate.
One problem in fitting door handle assemblies, particularly in the case where concealed mountings are employed, is ensuring that the escutcheon plates are properly aligned relative to the latch so that the handle shaft and the handles will be properly centred relative to the escutcheon plates and will not bind thereon. In order to meet this problem there have been developed latches formed with openings to receive posts extending between the escutcheon plates, or between a pair of escutcheon plate mounting discs, so that when the posts are engaged with these openings the escutcheon plates are properly centred on the latch opening which receives the handle shaft. In order to make use of a latch in this way it is necessary to drill three holes in the door, one for the handle shaft and two for the posts which are to engage the alignment openings in the latch, or to provide a single relatively large diameter opening which will receive both the shaft and the posts. The provision of a single opening is more common and, in fact, there is a growing tendency for doors to be supplied pre-drilled with large diameter holes. These holes are commonly 21/8 inches in diameter. However, not all doors are pre-drilled nor are all latches provided with alignment openings and there is therefore a need for a universal mounting means which can suit all combinations of door and latch. The present invention enables such a universal mounting means to be achieved.